NF-κB activation participates in the activated Akt signaling induced cardiac hypertrophy in vivo

AIM: To explore whether NF-κB activation participates in the activated Akt signaling-induced cardiac hypertrophy in vivo. METHODS: We used two in vivo models of cardiac hypertrophy, namely, aortic banding in Sprague-Dawley rats for 3 weeks and transgenic mice with cardiac specific expression of constitutively active Akt (caAkt). Electrophoretic mobility shift assay (EMSA) was used to determine NF-κB binding activity with nuclear proteins extracted from heart tissues. Western blots were performed to examine the phosphorylation of Akt and phosphor-IκBα with appropriate specific anti-phospho antibodies. RESULTS: ① The heart weight/body weight (HW/BW) ratio was significantly increased by 34.5% (P<0.01) in aortic banded 3 weeks rats compared to sham operated control. The level of phosphor-Akt in hypertrophic heart was significantly increased compared to sham operated control (P<0.01). ② The ratio of HW/BW in caAkt transgenic mice was significantly increased by 123.4% (P<0.01), compared to wild type control. NF-κB binding activity and the level of phospho-IκBα were also significantly increased in caAkt mice compared to wild type control (P<0.01). CONCLUSION: NF-κB activation participates in the activated Akt signaling-induced cardiac hypertrophy in vivo.